For collection undisturbed samples of 38mm dia for triaxial strength
and unconfined compressive strength either straight from the field
or from a sample of larger diameter. The wall thickness is maintained
approximately 17 per cent. Both relieved and unrelieved sampling
tubes are available. In the relieved type of tube, the internal diameter
is relieved by about 0.5mm (inside clearance 2%) beyond approx.
19mm length from the cutting edge of the tube. This is most suitable
for highly cohesive soils. In the unrelieved type, the internal diameter
is uniform through out. This type is most suitable for soil of low
cohesion. These 38mm dia tubes are available in different lengths.
UNRELIEVED
(a) 150mm,
(b) 200mm,
(c) 225mm
(d) 300mm long.
RELIEVED
(a) 150mm
(b) 200mm,
(c) 225mm,
(d) 300mm long.